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Counter-examples to the fractal Weyl law for semiclassical resonances
No full textUnder general assumptions, the numbers of semiclassical resonances is known to be bounded from above by a negative power of which is given by the fractal dimension of the trapped set. In this paper we provide examples of operators with much less resonances, showing that these upper bounds are not always sharp
Scientific opinion of the French Agency for Food, Environmental and Occupational Health and Safety on updating the state of the evidence on the prevention of neural tube defects through vitamin B9 intake
No full textANSES: Request No 2023-SA-0019International audienceFollowing a request from the French Directorate General for Health, ANSES was asked to deliver a scientific opinion on the state of the evidence on the prevention of neural tube defects (NTDs) by increasing vitamin B9 intake. The opinion estimates the prevalence of NTDs in France using data collected between 2012 and 2021 from five French registries reporting a mean prevalence of 13.5 per 10 000 births. The efficacy of vitamin B9 supplementation and food fortification was evaluated by conducting systematic reviews of human studies. The opinion also provides a comparative analysis of international vitamin B9 fortification strategies, followed by simulations to assess fortification levels and their potential to reduce inadequate vitamin B9 intake in France. The Expert Committee and ANSES concluded that fortifying flour (both refined and whole grain) with 200 μg of folic acid per 100 g would enable 90% of women to meet the Dietary Reference Value for adults and ensure a mean intake exceeding the adequate intake of 600 μg/day of dietary folate equivalents during pregnancy. However, this measure would not replace the recommendation for women to take a folic acid supplement (400 μg/day) from the moment they try to conceive until 12 weeks of pregnancy. ANSES further recommended initiating a public consultation of all the stakeholders
Scientific Opinion of the French Agency for Food, Environmental and Occupational Health & Safety on the establishment of dietary guidelines for people following a diet that excludes some or all foods of animal origin (vegetarians)
No full textInternational audienceThis document presents the opinion of the French Agency for Food, Environmental and Occupational Health & Safety (ANSES), established from the work of its Working Group on Vegetarian diets and validated by its Expert Committee on Human Nutrition. ANSES issued an internal request to establish dietary guidelines for people who follow a diet that excludes some or all foods of animal origin. Firstly, ANSES conducted a systematic review of the scientific literature to identify epidemiological links between health and various types of vegetarian diets. This systematic review showed that the risk of developing type 2 diabetes is lower with vegetarian than with non‐vegetarian diets. With a lower level of evidence, vegetarians are less likely than non‐vegetarians to develop certain diseases, such as ischaemic heart disease, ovulation disorders, certain types of cancer (prostate, stomach, blood) and certain ophthalmological and gastro‐intestinal diseases. However, they are at greater risk of bone fractures and hypospadias (congenital malformation of the urethra). The epidemiological studies examined showed that vegetarians have a less favourable nutritional status in iron, iodine and vitamins B12 and D, and a poorer calcium and phosphorus balance than non‐vegetarians. Vegans also have a less favourable nutritional status in vitamin B2. ANSES then used dietary optimisation to identify combinations of food groups (state variables) enabling the set objectives to be met, i.e. to reduce nutritional and toxicological risks, while deviating as little as possible from current consumption habits. All the nutritional and toxicological constraints and the criteria (minimisations or maximisations) made it possible to take account of the risks associated with nutrient intakes or exposure to contaminants, as well as the expected nutritional benefits. The systematic review and establishment of dietary guidelines using an optimisation tool show that the lacto‐ovo‐vegetarian diet requires particular attention regarding certain nutrients for which requirements in terms of vitamin D and eicosapentaenoic and docosahexaenoic fatty acids may not be met. The risk of requirements not being met by the lacto‐ovo‐vegetarian diet is greater than that associated with the diet of non‐vegetarian populations. In addition, lacto‐ovo‐vegetarians limiting their intake of milk and fresh dairy products may not be able to cover their vitamin B12 requirements. Furthermore, with the vegan diet, which excludes all foods of animal origin, it is difficult to meet the dietary reference value for zinc in men
An Introduction to Innovation and Circulation of Acupuncture (XIX - XXI Centuries): Between Governance and Personal Itinerary
No full textQuasi-amorphous crystal
No full textBrittle plastic yielding is a salient feature of well-annealed glassy materials. Here we show that the same behavior is characteristic of perfect crystals after they experience mechanically driven elastic instability leading to massive nucleation of dislocations. We argue that such 'preparation' effectively converts an atomic configuration from crystalline to quasi-amorphous. To understand the nature of the subsequent mechanical response, which is reminiscent of quasi-brittle yielding we study an athermal model 2D crystal subjected to quasistatic loading. We show that the intermittent pre- and post-yield dislocation avalanches exhibit power law statistics with matching exponents. The computed value of these exponents is indicative of marginal stability
Understanding health innovation adoption: a realist evaluation of pulse oximeter implementation in primary care for children under 5 in four West African countries
No full textInternational audienceIntroduction Hypoxaemia is an important contributor to child mortality, particularly in low-resource settings where diagnostic tools are scarce. The Améliorer l'Identification des détresses Respiratoires chez l'Enfant project introduced pulse oximeters (POs) into 202 primary healthcare centres (PHCs) in Burkina Faso, Guinea, Mali and Niger, integrating them into the Integrated Management of Childhood Illness guidelines. This initiative aimed to strengthen diagnostic capacities for identifying hypoxaemia and to improve care management for critically ill children under 5. This study examined how healthcare workers (HCWs) adopted POs and explored the contexts and mechanisms influencing their adoption. Methods We conducted a realist evaluation to analyse adoption patterns, focusing on interactions between the Intervention, Contexts, Actors, Mechanisms and Outcomes (ICAMO configurations). Data collection included 299 interviews with HCWs, patients’ families and institutional actors, conducted in 16 selected PHCs, at the institutional level and in district hospitals, complemented by site observations. Analysis was performed using NVivo software, identifying ICAMO configurations as demi-regularities to explain variations in PO use and adoption. Results Training enabled HCWs to recognise the utility of POs, further motivating their use. Support-focused supervision fostered a sense of support, while control-focused approaches sometimes resulted in mechanical use driven by external pressure. In contexts of high workloads and children’s agitation, difficulties in using POs were observed. In settings with limited diagnostic tools, POs increased HCWs’ diagnostic confidence, encouraging adoption and improving decision-making. Observing or knowing the benefits of POs on children’s health provided HCWs with a sense of relief and pride, further reinforcing PO adoption. However, structural barriers and challenges related to institutional adoption may threaten long-term use. Conclusions This study sheds light on the contexts and mechanisms that influence the use and adoption of the PO in PHCs. While widely used by HCWs, addressing challenges related to training, supply chain logistics and referral systems to hospitals is essential to ensure long-term sustainability and improve child health outcomes
The Legitimacy of Acupuncture in France: A Medical Innovation Under the Aegis of Tradition (Late Nineteenth to Early Twenty-First Centuries)
No full textInternational audienceThe evolution of “traditional” medicines frequently involves transnational circulation, appropriation, and the redefinition of their knowledge and techniques by local cultures. This dynamic is particularly evident in therapeutic practices originating from Chinese medicine, such as acupuncture and moxibustion, massage, and the prescription of remedies derived from the Chinese pharmacopoeia. This article focuses specifically on the context of France, examining how knowledge and know-how related to Chinese medicines have been constructed and how they circulate between the mid-twentieth century and the beginning of the twenty-first. Furthermore, this article explores how Chinese medical thought and practices developed during different historical periods were also conditioned by the professional orientation and intellectual aims of the different key figures of this medical knowledge. By analysing individual itineraries (Jami 2017) of these key figures, this article shows how a distinct medical knowledge and practice, identified as “French Traditionalist Acupuncture,” emerged in France influenced the medical landscape of acupuncture practices throughout Europe up to the present day
Webinaire scientifique, Vulnérabilités à l'université. Récits de persévérance et effets du dispositif de recherche participative.: Paroles d'étudiants à l'université Sorbonne Paris Nord
No full textInternational audienceNotre communication s’appuie sur une recherche participative intitulée « Expériences comparées de vulnérabilités territoriales : trajectoires d’étudiants et savoirs transformateurs (France-Brésil-Italie) » dans le cadre de l’Appel à Projets Commun MSH Paris Nord/Campus Condorcet (2024). Menée en collaboration avec 30 étudiants du master en Sciences de l’Éducation et de la Formation de l’USPN inscrits dans le parcours Insertion, Intervention sociale sur les Territoires, elle porte sur les vécus de vulnérabilités des étudiants ainsi que sur les freins et les leviers de la persévérance aux études. Dans un 1er temps nous présenterons le chemin de pensée ou la construction du cadre théorico-méthodologique (Dire et Agir) ; puis nous reviendrons sur quelques éléments saillants des récits d’étudiants, des formes et situations de vulnérabilité rencontrées ainsi que les ressources qu’ils développent ; nous aborderons enfin certains effets transformateurs entre réappropriation d’une histoire, élaboration d’une identité personnelle et collective, et développement d’un pouvoir d’agir
Prognostic impact of the number and Temporality of heart failure Hospitalisations: Analysis of a National healthcare database
No full textInternational audienceAims: To assess the prognostic impact of both the frequency and timing of prior heart failure (HF) hospitalisations on outcomes in patients with reduced left ventricular ejection fraction (LVEF).Methods and results : This nationwide retrospective cohort study used the French national health insurance database to identify 730,052 adults with HF in 2017. A validated algorithm classified 226,747 as HF with reduced LVEF (<45 %), of whom 54,504 (24 %) had at least one HF-related hospitalisation >24 h within the preceding 24 months (worsening HF group). Patients were stratified by (1) time since the last HF hospitalisation (0–6, 6–24 months) and (2) number of hospitalisations (1, 2, ≥3). Mean age was 76 ± 15 years. Prior HF hospitalisation was the strongest predictor of mortality among all variables. After multivariable adjustment, prior hospitalisation was associated with increased risk of all-cause death (HR 1.61, 95 % CI 1.56–1.65), all-cause hospitalisation (HR 1.34, 95 % CI 1.32–1.37), and recurrent HF hospitalisation (HR 2.51, 95 % CI 2.43–2.59). Risks were greatest when the most recent hospitalisation occurred within 6 months and rose progressively with the number of prior events.Conclusion : In patients with reduced LVEF, both recent and recurrent HF hospitalisations are strong predictors of mortality and rehospitalisation. These two simple markers identify highly vulnerable patients and should trigger intensified follow-up, optimisation of guideline-directed therapies, and implementation of transitional care and remote monitoring programs
Galois representations modulo that do not lift modulo
No full textInternational audienceFor every finite group H H and every finite H H -module A A , we determine the subgroup of negligible classes in H 2 ( H , A ) H^2(H,A) , in the sense of Serre, over fields with enough roots of unity. As a consequence, we show that for every odd prime p p , every integer n ≥ 3 n\geq 3 , and every field F F containing a primitive p p -th root of unity, there exists a continuous n n -dimensional mod p p representation of the absolute Galois group of F ( x 1 , … , x p ) F(x_1,\dots ,x_p) which does not lift modulo p 2 p^2 . This answers a question of Khare and Serre, and disproves a conjecture of Florence